Firearm with aluminum barrel and receiver



Feb. 28. 1956 R. E. CLARKSON ET AL 2,736,117

FIREARM WITH ALUMINUM BARREL AND RECEIVER 2 Sheets-Sheet 1 Filed Dec. 181951 Feb. 28, 1956 R. E. CLARKSON ET AL 2,736,117

FIREARM WITH ALUMINUM BARREL AND RECEIVER Filed Dec. 18, 1951 2Sheets-Sheet 2 ijnited States Patent Ofiice 2,736,117 Patented Feb. 23,1956 FIREARM WITH ALUMINUM BARREL AND RECEIVER Ralph E. Clarkson,Hamden, and Tuines W. van Wilgen, Branford, Conn., assignors to OlinMathieson Chemical Corporation, a corporation of Virginia ApplicationDecember 18, 1951, Serial No. 262,281

Claims. (CI. 42-75) This invention relates to firearms, and particularlyto repeating or semi-automatic shotguns, and has for its object theprovision of improvements in the receiver and in the barrel connectionto the receiver to effect a reduction in weight without sacrificingstrength. Our invention provides a means, which, for convenience, weshall refer to as the liner-chamber, comprising an improved chambermember with means for connecting the barrel thereto, and a receiverliner integral with the chamber member for insertion into the receiver.

In a preferred embodiment, the liner-chamber is a unitary structure withmeans for the removable connection of the barrel to the chamber memberand for locking the breech block to the receiver liner. On importantfeature of the invention is the provision of a shoulder, such as anannular shoulder, on the unitary liner-chamber against which thereceiver extension abuts and can, therefore, always be secured in exactoperative position with respect to the chamber member.

The invention provides a combination of the receiver liner of anysuitable construction, the receiver liner being constructed and arrangedto receive the impact of the explosion on the breech block, thuspermitting the use of a receiver constructed of lightweight or lowstrength materials. The invention also provides a combination of theliner-chamber with a barrel of any suitable type, and the barrel may beconnected to the chamber member in any manner, advantageously byhalf-threads to facilitate rapid connection and removal. The unitaryconstruction of the liner-chamber provides a rigid, strong connectionbetween the breech block and the chamber member, and the chamber memberis advantageously constructed to receive the major force of theexplosion. We are, therefore, able to use relatively very lightweightbarrels, such as those made of very thin steel or aluminum alloys, thuseffecting a material reduction in the weight of the gun. V

The invention is advantageously applicable to firearms having a breechblock with locking means engageable with a shoulder in the receiver. Oneof the important advantages of the invention is that the breech blocklocking shoulder is in the receiver liner and the breech block may bemounted in the receiver liner and fitted for head-spacing prior tomounting in the receiver or attaching to the barrel. The unitaryconstruction provides fixed dimensions between the breech block lockingshoulder and the chamber. An advantage in this construction is that inusing the liner-chamber of the invention in such receivers as that ofthe model 12 Winchester shotgun the difficult head-spacing is materiallysimplified.

Although the invention is advantageously applicable to various types ofrepeating or semi-automatic firearms, for the purpose of illustrationthe unitary liner-chamber in combination with a receiver and with abarrel will be shown and described in connection with the model 12Winchester repeating shotgun.

These and other novel features of the invention will be betterunderstood after considering the following discussion taken inconjunction with the a ccompanying drawings, in which:

Fig. 1 is a side view of the major portion of a model 12 Winchesterrepeating shotgun;

Fig. 2 is an enlarged fragmentary view, partly in section, of theshotgun of Fig. l with parts removed;

Fig. 3 is an exploded fragmentary side view of the liner-chamber andbarrel, partly in section;

Figs. 4 and 5 are sectional views at 3-4 and 5-5, respectively, of Fig.2;

Fig. 6 is an enlarged fragmentary sectional view, partly in section, at6 of Fig. 2;

Fig. 7 is a perspective of the receiver extension;

Fig. 8 is a perspective from the forward end of a linerchamber of theinvention, and

Fig. 9 is a perspective of the barrel from the chamber end.

The model 12 shotgun illustrated in the drawings comprises a receiver 1,a breech block 2, barrel 3, receiver extension 4, magazine tube 5, andaction slide handle 6. The details of the action and firing mechanismare omitted from the description as they are well known and unnecessaryin understanding the invention. Any suitable devices of that charactermay be used depending upon the type of gun in which the invention isused. As best shown in Figs. 2, 3 and 6, the liner-chamber 7 is aunitary structure formed, for example, of high strength alloy steel,beryllium bronze, and the like, and comprises as principal parts thechamber member 8, the receiver liner 9, and an annular rib 10. Thereceiver liner 9 is suitably cut out or fashioned for receiving theparticular breech block used for blocking the breech and to provideopening means for loading shells into the chamber and ejecting the casesafter firing. The receiver liner, in its broader aspects, is a rigidextension of the chamber member for effecting a secure and preferablydetachable connection to the receiver, and also to effect a lockingconnection with the breech block. While the unitary construction is mostadvantageous and preferred for most purposes, we may construct thereceiver liner and chamber member as separate parts and connect theminto an integral structure, as by threads or welding. Hereinafter, whenwe refer to an integral liner-chamber, we include one formed of twoconnected parts or a unitary structure. The linerchamber has a threadedsection 15 by means of which the entire structure 7 is securely attachedto the receiver 1, including locking shoulder 16 for the breech block.In its assembled position in the gun, the annular rib 10 is brought intotight contact with the receiver end-surface 17, thus providing adefinite fixed space between the chamber member and the means in thereceiver (not shown) for operating the breech block. Moreover, theunitary structure prior to installation, as shown in Fig. 8, can befitted to its breech block for head-spacing very advantageously as theshoulder 16' is easily accessible for any trimming that may benecessary.

The chamber member comprises an inner bore 18 which is the actualshellchamber, a relatively thick wall portion 19 and a necked forward endportion 20 surrounding the bore 18, and the two half thread sections 21and 22 on the Wall portion. The necked portion 20 may be relatively thinat its extreme edges, say, from 0.030 to 0.040 inch thick, and in afairly snug contact with the barrel so that the neck can expand withinits elastic limits into sealing contact with the barrel. We may select amaterial for the chamber member having a modulus of elasticity which, incomparison with the modulus of elasticity of the barrel, will effectgood sealing contact on expansion. The unitary linear-chamber whenmounted in the receiver, as shown at the left Fig. 3, has the rigidchamber member 8 projecting forward.

As a point of interest illustrative of the construction and function ofthe liner-chamber, a shell could be inserted into the chamber member,the breech block locked in the receiver liner, and the liner-chamberheld by any securing structure, such as a vise, and fired because thereceiver liner is the essential loading-carrying medium. We may,accordingly, form the receiver of plastic material, any light metal suchas aluminum, steel stampings, or malleable iron castings. We may alsouse any high strength molded or laminated material, such as bonded glassfibers, which have dampening characteristics. The barrel may be made ofa very thin strong metal such as steel, or of a light metal such asaluminum. We prefer to use a high strength aluminum alloy rod or barstock formed of alloys such as 14S-T, 17S-T, 75S-T, 24S-T, 24S-RT, andR303-T, and we may treat the aluminum, especially for the barrel,according to any suitable anodizing process. The barrel may be formed ofa high strength alloy such as 75S-T which has a cladding of relativelypure aluminum either inside or outside to reduce shattering of the lessductile 75S-T. The barrel is coupled by means of half-threads (with orwithout pitch) directly to the complementary half-threads 21 and 22 ofthe chamber member or by other suitable means.

In the embodiment illustrated, the receiver extension 4 is used toeifect a very practicable connection of the barrel, magazine tube andslide handle for quick takedown purposes. The receiver extension 4 hasinterior threads 25 for engaging the exterior threads 26 on the barrel.When the receiver extension is screwed into position on the barrel withthe face 27 in tight engagement with the shoulder 28 of the barrel, theopposite face 29 of the receiver extension is in close contact with theforward face of the annular rib 10. The receiver extension has a tubularextension 32 in which the magazine tube is in slidable connection. Themagazine tube has halfsection lugs 33 and 34 for engaging complementaryhalfsection lugs in the receiver, as shown in Fig. 2, which hold thereceiver extension on the receiver in a nonturnable position.

In disconnecting the barrel, receiver extension, and magazine, thelocking pin 35 is disengaged, the magazine tube is given a quarter turnand is pulled forward out of its threaded recess in the receiver. Thebarrel, magazine, and receiver extension can then be given a one-quarterturn to disengage the half-threads 21 and 22 and the barrel can beslipped off the chamber member.

We claim:

1. A liner-chamber for firearms comprising in integral connection achamber member having means for removably connecting a barrel thereto infixed operative position i and a receiver liner having means forattaching to the receiver of a gun in a fixed operative position and forthe operation of a breech block therewith, said chamber member having awall portion which will contain the force of an explosion therein, and anecked portion at its forward end that is expansible intocontact with asurrounding barrel at the time of explosion, said chamber wall portionbeing appreciably thicker than the necked portion.

2. A liner-chamber according to claim 1 comprising threads on thechamber member for the connection of a barrel thereto and threads on thereceiver liner for connection to a receiver.

3. A liner-chamber according to claim 1 comprising a rib for effectingabutting engagement with the receiver.

4. A liner-chamber according to claim 1 which comprises half-threads onthe exterior of the chamber member for the removable attachment of thebarrel thereto.

5. The combination in shotguns which comprises a receiver, an integralliner-chamber comprising a chamber member and a receiver liner, threadmeans for mounting the receiver liner in a fixed position in thereceiver with the chamber member extending forwardly beyond thereceiver, means on the chamber member for securing a barrel in anoperative immovable position over the chamber, said chamber memberhaving a Wall section capable of containing the force of an explosiontherein and a necked wall section at its forward end that is expansibleinto a sealing contact with the surrounding barrel at the time ofexplosion, said first-mentioned wall section being appreciably thickerthan the necked wall section.

6. The combination according to claim 5 which comprises an annular ribon the liner-chamber that effects abutting engagement with the receiver,a receiver extension in threaded connection with the exterior endportion of the barrel, threads on the exterior of the chamber member forscrewing the barrel thereon until the receiver extension makes abuttingcontact with the annular rib.

7. The combination according to claim 5 in which the barrel is formed ofaluminum and the liner-chamber is formed of steel.

8. The combination according to claim 5 in which the receiver is formedof aluminum and the liner-chamber is formed of steel.

9. The combination in shotguns which comprises an aluminum receiver, aunitary liner-chamber having a receiver liner and a chamber liner, thereceiver liner having a breech block and locking means therefor andbeing in threaded connection with the receiver, a rib on thelinerchamber located at the junction of the receiver liner and thechamber liner, exterior threads on the receiver liner and on the chamberliner, said receiver liner being threaded into the receiver, an aluminumbarrel having interior threads in threaded connection with the chamberliner which is inserted into the barrel, said rib being in abuttingengagement with thereceiver and the barrel being in abutting engagementwith the rib, said chamber liner having sufficient structural strengthto contain the pressure of the explosion independently of the barrel.

10. The combination in shotguns which comprises an aluminum receiver, aunitary liner-chamber having a receiver liner in fixed operativeconnection to the receiver and a chamber liner for insertion into abarrel with removable connection thereto, said connections being injuxtaposition on the exterior of said unitary liner-chamber, breechblock locking means on the receiver liner, a breech block in operativeengagement in the receiver liner, said connecting means effecting afixed relation between the receiver, liner-chamber and barrel, and analuminum barrel in said removable but operatively fixed connection withthe chamber member, at least a portion of the chamber liner extendinginto the barrel being expansible into contact with the barrel at thetime of explosion, whereby the force of the explosion on the breechblock is absorbed by the receiver liner and the major pressure of theexplosion is contained by the chamber member.

References Cited in the file of this patent UNITED STATES PATENTS781,765 Browning Feb. 7, 1905 1,234,783 Mauser July 31, 1917 1,628,798-Nelson May 17, 1927 1,864,374 Romberg et al. June 21, 1932 2,440,634Henney Apr. 27, 1948 2,476,232 Williams July 12, 1949 FOREIGN PATENTS831,030 France May 30, 1938 OTHER REFERENCES Stoegers Catalog, TheShooters Bible, 1940 ed., page 111.

